Status Report

USAF/NOAA Report of Solar-Geophysical Activity 25 Feb

By SpaceRef Editor
February 25, 2000
Filed under

:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Feb 25 2210 UT
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
#Space Environment Center and the U.S. Air Force.
#
JOINT USAF/NOAA REPORT OF SOLAR AND GEOPHYSICAL ACTIVITY
SDF NUMBER 056 ISSUED AT 2200Z ON 25 FEB 2000
IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 24/2100Z
TO 25/2100Z: SOLAR ACTIVITY BECAME LOW. THE LARGEST EVENT OF THE
PERIOD WAS A MODERATE DURATION C8/SF AT 25/0919Z FROM REGION 8888
(N36E43). A CORONAL MASS EJECTION ACCOMPANIED THIS EVENT BUT WAS
DIRECTED OUT OF THE ECLIPTIC. OTHER THAN THIS EVENT, THE REGION WAS
MOSTLY STABLE DURING THE PERIOD. REGION 8889 (N21E59) SHOWED ITSELF
AS A MODERATE SIZE E CLASS GROUP AND PRODUCED SMALL C-CLASS
SUBFLARES. A LARGE NEW REGION ROTATED OVER THE EAST LIMB AT S13E72
AND WAS NUMBERED AS REGION 8891. THIS AREA WAS PREDOMINANTLY STABLE
DURING THE PERIOD. THERE WERE ALSO HIGH LATITUDE MASS EJECTIONS FROM
THE NORTHWEST AND SOUTHEAST LIMBS DURING THE PERIOD.
IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY SHOULD RETURN TO
MODERATE LEVELS. M-CLASS EVENTS ARE POSSIBLE FROM REGIONS 8891,
8889, AND TO A LESSER DEGREE, REGION 8888. THERE IS A SLIGHT BUT
GROWING POSSIBILITY OF A MAJOR FLARE FROM REGIONS 8891 AND 8889.
IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 24/2100Z TO 25/2100Z:
THE GEOMAGNETIC FIELD WAS PREDOMINANTLY UNSETTLED TO ACTIVE. ISOLATED
PERIODS OF MINOR STORMING WERE OBSERVED. SOLAR WIND VELOCITY
DECREASED DURING THE PERIOD BUT REMAINED ELEVATED ABOVE 650 KM/S.
ENERGETIC ELECTRON FLUXES AT GEOSYNCHRONOUS ORBIT BECAME HIGH AROUND
25/1710Z.
IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD SHOULD
REMAIN PREDOMINANTLY UNSETTLED TO ACTIVE WITH BRIEF PERIODS OF MINOR
STORMING FOR 26 FEB. THE CURRENT DISTURBANCE SHOULD SLOWLY DECLINE
ON 27-28 FEB. QUIET TO OCCASIONALLY ACTIVE CONDITIONS ARE EXPECTED
DURING THAT PERIOD. ENERGETIC ELECTRON FLUXES SHOULD REMAIN ELEVATED
FOR A MINIMUM OF THE NEXT THREE DAYS.
III. EVENT PROBABILITIES 26 FEB-28 FEB
CLASS M 75/75/75
CLASS X 15/15/15
PROTON 05/05/05
PCAF GREEN
IV. PENTICTON 10.7 CM FLUX
OBSERVED 25 FEB 210
PREDICTED 26 FEB-28 FEB 213/215/218
90 DAY MEAN 25 FEB 165
V. GEOMAGNETIC A INDICES
OBSERVED AFR/AP 24 FEB 020/026
ESTIMATED AFR/AP 25 FEB 020/020
PREDICTED AFR/AP 26 FEB-28 FEB 018/018-012/015-008/013
VI. GEOMAGNETIC ACTIVITY PROBABILITIES 26 FEB-28 FEB
A. MIDDLE LATITUDES
ACTIVE 50/40/30
MINOR STORM 25/15/10
MAJOR-SEVERE STORM 05/05/01
B. HIGH LATITUDES
ACTIVE 50/40/30
MINOR STORM 25/15/10
MAJOR-SEVERE STORM 05/05/01

SpaceRef staff editor.